Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
151 AM EST Wed Feb 02 2022
Valid 12Z Sat Feb 05 2022 - 12Z Wed Feb 09 2022
...Overview...
The medium range period starts out Saturday with broad troughing
across much of the CONUS, sandwiched between a building ridge over
the East Pacific and a retreating ridge into the west-central
Atlantic. Within the mean flow, multiple smaller scale shortwaves
should be present -- one exiting the Northeast, another weakening
into the Deep South, and a third dropping into the northern
Rockies. The last one should amplify by early next week with a
positively tilted trough stretched from the Great Lakes to the
Southern Plains. Southern stream energy out of this trough may
move across the Southeast to induce surface low cyclogenesis well
off the East Coast. Meanwhile, strong ridging will build in across
the West (and points east) before dropping southward as the next
shortwave moves across the northern tier by the middle of next
week.
...Guidance Evaluation/Predictability Assessment...
The latest suite of models and ensembles continue to show enough
agreement for a general deterministic model blend for the day
3-5/Saturday-Monday time period. After this, timing differences
remain with a northern stream shortwave across the northern Plains
on Tuesday, though models did trend slightly faster than previous
WPC continuity. Elsewhere, there has been plenty of run to run
variability with another Southeast shortwave on Tuesday and also
an exiting shortwave through the Northeast. Given what are mostly
small scale detail differences with these systems, it seemed most
advantageous at this stage to blend in more of the ensemble means
the latter half of the period. This approach maintains good
continuity with yesterdays WPC forecast as well.
...Weather Highlights/Threats...
Much of the CONUS should be uneventful and mostly dry through
early next week at least in terms of any notable weather threats.
Periodic activity is possible across the Southeast associated with
a couple of frontal waves/upper level impulses. However, continued
guidance differences leads to low confidence in the coverage and
amounts of precipitation over the region. Enough cold air however
does offer the potential for some swaths of wintry weather on the
northern periphery of any kind of surface low development off the
east coast, with the best potential for any kind of light activity
on Sunday over the Carolinas or southern Mid-Atlantic. Elsewhere,
northern tier systems will bring periods of light and scattered
snow from the upper Midwest to Great Lakes while mostly light
rain/mountain snow should accompany a couple of systems brushing
the Pacific Northwest and northern Rockies.
Much below normal temperatures, with daytime highs as much as 10
to 20 degrees below normal, will continue through the weekend
across parts of Texas, with less extreme, but still below normal,
values extending eastward to the East Coast. After Sunday,
temperatures across this region should moderate back towards
normal. A welcome relief from the cold in the short range period,
the northern to central Plains should remain above normal through
the entire medium range period, with the warmest anomalies
(+20-25F) during the first half of next week as upper level
ridging moves in. Meanwhile, the western U.S. should trend warmer
as well under the influence of eastern Pacific ridging making its
way onshore.
Santorelli
Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards outlook chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php
WPC medium range 500mb heights, surface systems, weather grids,
quantitative precipitation, winter weather outlook probabilities
and heat indices are at:
https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif
https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html
https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml
https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4
https://www.wpc.ncep.noaa.gov/heat_index.shtml